A TRIAL TO COMPARE OXALIPLATIN, FOLINIC ACID (FA) AND 5-FLUOROURACIL (5FU) COMBINATION CHEMOTHERAPY (FOLFOX-4) WITH OR WITHOUT CETUXIMAB IN THE 1ST LINE TREATMENT OF METASTATIC COLORECTAL CANCER (MCRC) IN CHINESE RAT SARCOMA VIRAL ONCOGENE HOMOLOG (RAS) WILD-TYPE PATIENTS: